Production of brewers&#39; wort



March 1963 G. A. DUMMETT ETAL 3,

PRODUCTION OF BREWERS WORT 2 Sheets-Sheet 1 Filed March 21, 1960 Q 3 VNM EH M In ventorJ a m/mdt flaw A ttorneyr w w .w

March 19, 1963 G. A. DUMMETT ETAL 3,032,090

PRODUCTION OF BREWERS WORT Filed March 21, 1960 v 2 Sheets-Sheet 2 v E i1 w a v a KR N E N w e Invenlorr JW M 37 6mm 4 71 Attorney.)-

United States Patent O 3,082,090 PRODUCTION OF BREWERS WORT GeorgeAnthony Dummett, Fairwarp, near Uckfield, and

David Teignmouth Shore, Banstead, England, assignors to The A.P.V.Company Limited" Filed Mar. 21, 1960, Ser. No. 16,281 Claims priority,application Great Britain Mar. 2.0,v 1959 r r 1 Claim. (Cl. 99-52) Thisinvention relates to the production of brewers wort in the mashing stageat which a liquor, known as sweet wort isproduced, from a mixture ofliquid (usually water) and'a'malt grist, by a process of conversion andextraction, the sweet wort passing on after filtration for furtherprocessing.

Modern development ofbrewery' practice requires that the liquor shall"be in continuous progression through this mashing stage as well as theother stages of treatment: it is however essential that the mixture ofliquor andmalt shall be held at a certain temperature or range oftemperatures during this mashing action and also that the mixture shallbe allowed to remain more or less undisturbed for a time interval whichis sufiicient to enable the necessary extraction and enzymic reactionsto occur.

These requirements are met in accordance with the present invention byfeeding the mixture of liquor and malt continuously to a duct which isequipped with means such as a heating jacket or a number of heatingjackets along its length so as to enable the temperature of the mixtureas it flows in the duct to be held at a predetermined value or valuesduring the conversion and in addition the duct is so dimensioned that agiven mixture although moving continuously through the duct will remainundisturbed as to the suspension of the solids or semisolids in themixture and will move at a rate such that the desired conversion will bemore or less completed while in the duct; .7 1

The malts used in the brewing industry ditfer considerably in characterand in many instances the grist consists of cereals which are eithermashed in with malt or cooked separately before being added to the mainbrew. For most British beers the adjuncts with the malt are mashed in asingle stage. During the conversion process occurring in the flow intheduct for continuous mashing, different time/temperature cyclesare-required to enable a close control to be exercised over the ratio offermentable to unfermentable sugars and also other chemical changestaking place in the particular mash benig treated and the inventionenables that control to be readily obtained; Y

The temperature control can be achieved by a heating jacket disposedabout the duct and included in a flow of temperature control-medium thetemperature of which is regulatedto produce the desired. reaction or itcould comprise electrically energised elements.

Again provision could be made to withdraw a part of the plug fiow in theduct, passing the withdrawn flow in indirect heat exchange with aheating or cooling medium and then returning the now temperatureconditioned flow to the duct.

The said means could be arranged so to control the temperature that ithas the same predetermined value over the length of the duct or it couldbe arranged to enable the temperature so to be controlled as to havedifferent values at different zones in the length of the duct. Thetemperature control could be obtained by constituting the duct (regardedas such in the overall flow) by a number of separate but interconnectedducts each having its own temperature control: in addition for certainproducts the component parts making up the product when they arecombined could flow, in plug Fee.

fashion as determined by the size of the duct througl separate ductshaving their own temperature control the out-put of the ducts beingcombined in a flow througl a further duct or ducts also havingtemperature control: this latter arrangement could be used for brewingContinental and other beers in which large quantities o1 starch materialare employed. In such cases the starcl material is not necessarilymashed with the malted mate rial but is separately cooked before mixingwith the malt mash.

In such cases the starch material could be masher by the plug flow inits own duct which is heated tc cook the mash as it progresses throughthe duct.

Depending on the ratio of the malted to unmaltet material and also itsnature and composition, it may 'be necessary to mix the two mashes in asmall mixing vessel and then to pump the mixture to a tube masheraccording to this invention to establish the main conversion during plugflow, The use of this mixing vesse and the pump ensures intimate mixingof the two mashe: so as to improve the conversion efficiency of starchtc sugars by avoiding concentration gradients of maltec to unmaltedmaterials in the mash. 7

By the invention therefore the time/ temperature cycle can be set tosuit the different requirements of the differ ent malts while at thesame time conserving the requiret plug flow. As an operatingcondition itis very desirablr that there shall be no large temperature gradients soa: to avoid the creation of turbulence in the plug flov of mixture whichtakes place in the duct. 1

When a jacket is used, the heating medium employec can be theattemperatured liquor which is produced it the beer brewing process butsteam or hot water fron other sources could be used. Thus, the inventionenable: the essential requirement of the mashing operation, i.e that themixture shall remain undisturbed during the re action, to be compliedwith while at the same time on abling the mashing action at determinedtemperatures t( be adapted to the requirements of modern processing witlits requirement for continuous movement of liquo:

' throughout the complete processing of wort to the fina fermentatingstage.

The precise form of the duct will of course depenr on the requirementand conditions required for complet mashing in any particular case: itcan however be sair that the duct must be such in relation to themixture am its rate of flow that the solid constituents of the mixturshall more or less interlock to form the plug. This in volves the ductsize to be selected to produce a rate 0 flow which depends on the ratioof grist to liquor in an particular case.

It has been found that when the conditions are selecte to produce thisplug formation of the mixture there i no preferential flow of liquor tosolids even when th flow is required to take place in swept bends whichma well have to-be provided in the duct to provide a built up length ofduct sufficient for the complete reactior There is however an intimatemixing of the constituent due to movement of the liquor in theinterstices betwee: the solids.

Not only does the invention enable the mashin process to be adapted forinclusion in the modern cor tinuous method of wort treatment but it alsoprovides more efficient mashing action than is given by the norm:process employing a mash tun.

The intimate mixing referred to above promotes rapid conversion whencompared with the convention: mash tun practice and furthermore enablesa much close temperature control to be eifected either on the who] mashor on a particular time cycle employed by th brewer.

The importance of creating the moving plug is empha ;ised by the factthat any breakdown in the plug has been found to result in apreferential fiow of liquid to solids resulting in instability, poorconversion to sugars and arobably to possible blockage of the duct bythe solids.

Experiments which have been made show that the rate at flow of themixture should be high rather than low as to reduce the effects of localdisturbances such as :ddies: thus by way of example the ducts can beselected :0 produce a rate of flow of between 1 and 48" per ninute whenthe duct is circular of diameters between and 12". Thus excellentresults have been obtained For the British mashing rate of between 22 /2barrels of .iquor per quarter of grist by using a duct in the form of tcircular tube having an internal diameter of 3" and a ,ength of 100 feetwhich can be made up of lengths of ,ube connected by bends.

Following the conversion stage in the flow in the duct Where closetemperature control has in conjunction with he holding periods enabled aclose control to be made )f the wort composition, a final section of theduct could )e heated to a temperature sufiicient to destroy further:nzymic activity and to prevent further changes of wort :ompositionduring a following filtration stage. This inal heating stage could bringthe temperature of the nash to at least 170 F., and in some cases maybring the nash to its boiling point.

The invention is illustrated in the accompanying drawngs which showdiagrammatically various installations all )f which make use of ductssuch as to create a condition )1? plug fiow.

In the installation shown in FIG. 1 a duct marked 1 'eceives a liquorcomprising a mixture of malt, cereal and hot water from a vessel 3, thesupply to the duct )eing effected by a pump 2. As has been described byt selection of the variables which are involved in estabishing a flow ofthe liquor through the duct 1, the mixure will advance continuouslyalong the duct in the form )f a plug and at a rate which will enable therequired reiction to take place during the flow in the duct although itthe same time the constituents remain quiescent or iensibly so.

In addition provision is made to enable the temperaure at which thereaction takes place to be regulated to :uit the different requirementswhich arise in different :ases. For that purpose, the duct 1 isjaeketted to receive I. heating or a cooling medium: the jacketting canexend over the complete length of the duct or as is shown 11 FIG. 1 theduct can be jacketted in various sections A, 3, C each having its ownsupply and discharge connecions 10, 11 by which the jackets can beincluded in a :irculation effected by pumps 12 of a temperature conrolmedium.

The temperature of the medium can be controlled by ndirect heat exchangewith a heat input or extraction nedium (such as steam) supplied to heatexchangers 13 )y flow lines 14.

The installation shown in FIG. 2 is arranged for the troduction of aproduct the components of which require to be separately cooked orotherwise subjected to heat action before the ingredients are mixed toprovide a mixture which itself requires to be subjected to some heating(or cooling) action.

In this case it will be assured that the components of the final mixtureconsists of an admixture of malted liquor forming a mash which isproduced in the vessel 15 and a mash consisting of starch or cerealliquor which is produced in the vessel 16. The two mashes are deliveredby pumps 2 to separate ducts 1, 1 which are such as to establish therequired plug flows of the two mashes and these plug flows are united ina duct 1 again dimensioned to establish the plug flow.

In such a case, the temperature conditions under which the reactions inthe two mashes take place during their plug flow in the ducts 1, 1 isregulated by jacketting those ducts as indicated at D, E: the jacket Dprovides a controlled temperature zone through which the malt mash flowswithout disturbance for a predetermined time: the jacket E provides asimilar controlled temperature zone for the treatment of the starch orcereal mash and enables that mash to be pre-treated independently of themalt mash.

The mixture of the two mashes then flows through the duct 1, which (asin the arrangement shown in FIG. 1) is provided with jackets A, B, C tocomplete the conversion during the plug flow through the duct 1, theproduct finally passing to a mash filter (not shown) of conventionalform.

In FIG. 3 is shown a modified installation which still relies on theprinciple of plug fiow but which consists in controlling the temperatureby withdrawing a part of the flow to subject it to a heating (orcooling) etfect and then returning that part of the flow to the mainflow. The installation in general follows that of FIG. 1 but the jacketsA, B, C are dispensed with, the various pumps 12 extracting a part ofthe plug flow from the duct through lines 17, and supplying it to theheat exchangers 13 the temperature controlled out-put of which isreturned to the duct 1 via the lines 18.

We claim:

Regulating the production of sweet brewers wort by the method whichcomprises continuously feeding different mixtures of grist and liquor todifferent ducts each of such cross-sectional dimension in relation tothe supply as to cause the mixture fed to the duct to advance as aquiescent plug in the duct, in controlling the temperature of themixture in each duct, in combining the out-put from the diiferent ductsand passing the collected mixture to a similar duct in which thetemperature of the plug flow is regulated to complete the conversion ofthe mixture while it is advancing as a plug flow in the said similarduct.

References Cited in the file of this patent UNITED STATES PATENTS

